1. Field of the Invention
The present invention relates to a satellite antenna, and more particular to a waterproof mechanism for a satellite antenna.
2. Description of Related Art
A general satellite antenna system is to place a low noise block with integrated feed (LNBF) at a plane where the focus of an antenna dish is located so as to receive satellite signals.
U.S. Pat. No. 6,570,542 discloses an integrated dual-directional feed horn, for receiving radio frequency (RF) signals from two satellites in a small angle, includes a first LNBF and a second LNBF.
U.S. Pat. No. 6,191,753 discloses a rigid cover for satellite antennas. The cover prevents rain from passing between a dish member and a converter assembly of the satellite antenna. The cover may be designed for a particular style of the satellite antenna. The cover may be designed for a particular style of satellite antenna or, preferably, have a mounting portion adapted to accommodate a plurality of styles of satellite antennas.
LNBF disclosed in U.S. Pat. No. 6,570,524 mentioned above has no design of a waterproof cap at the opening end of a wave-guide tube thereof so that rain flows easily into the inner part of the wave-guide tube to damage the LNBF.
A cover disclosed in U.S. Pat. No. 6,191,753 shields the signal receiving face of a whole dish member and a converter assembly. The design thereof allows the converter assembly not to be exposed to the rain, but because its cover shields the signal receiving face of the dish member, it would influence the satellite signal receiving effect. Furthermore, because the volume of the cover is very large, the production cost is rather high.
Because the LNBF is an outdoor product, for preventing the LNBF from being damaged by the rain, it is usually to collocate a waterproof cap in the front of the wave-guide tube of the LNBF to maintain the normal functions and the life of the LNBF.
Because the top thickness of the waterproof cap will influence the satellite signal receiving effect, there are two methods used at the present: an O-ring is used for combining between the waterproof cap and the wave-guide tube and adhesive is used for sticking a thin film and the wave-guide tube. The common used method is the design using O-ring combination because the method using the adhesive for combing is rather time wasting.
The practice using O-ring combination is to integrate an O-ring pressing mechanism with the waterproof cap. But, because of the limitation of the present mold injection, such kind of practice will cause the thickness of the top of the waterproof cap is rather thick to influence the receiving effect of signals. If we want the thickness of the top of the waterproof cap to be thinner, a thin film must be adopted. But, because the thickness of the thin film is thinner, it cannot be integrated with the pressing mechanism. If the thin film is forced to be integrated with the O-ring pressing mechanism, deformation and shrinkage are caused because the difference of the thick and the thin parts are overlarge to lead to the waterproof effect to be in vain. Therefore, the adhesive stuck method must be used for attaining to a waterproof effect, but it also increase the needed combining time.